Trapped beneath the Earth

For British cave divers, Chris Jewell and Jim Warny, who had been being rushed out to Thailand to help in this week’s epic rescue operation, the events bore an uncanny echo to a life-and-death struggle they had just recently experienced on the other side of the world

Two of the British divers working on the so-called ‘Mission Impossible’ to free the twelve schoolboys and their football coach from the Tham Luang cave in Thailand, had just returned home from a major expedition to Mexico in April and May this year where, in its closing stages, part of their team also became trapped underground by rapidly rising flood water.

Six elite divers found themselves literally running for their lives when unexpected rainfall suddenly started pouring into the Sierra Mazateca cave system they were exploring. The team ended up trapped a kilometre underground with no exit, very little food, and just the wetsuits they were wearing to provide protection.

‘I was humping gear in an area know as the Grand Lagoon deep inside the system when the silence was broken by a deafening noise, as if two giant water turbines had suddenly been turned on,’ says Andreas Klocker, 38, one of the expedition leaders. Klocker instinctively knew they were in trouble. Despite this being the dry season in Sierra Mazateca, an isolated mountainous region in the southern Mexico province of Oaxaca, the only explanation for the noise was that an unexpected downpour was rapidly filling the extremely challenging cave system.

Klocker immediately ran to Zeb, another team member who was bringing bad news of his own. ‘He immediately told me that the water level in Sump Three had just come up by almost a metre,’ Klocker recalls, referring to the flooded passages in a cave network that require the use of scuba gear to navigate. ‘Putting those two bits of information together – both the thundering noise at the Grand Lagoon and the fast-rising water in Sump Three – it was clear to me that we were in big trouble. My face must have looked worried, and Zeb, who has probably spent more time with me in very remote cave passages than anyone else, realised immediately that this was serious.’

The ‘Whacking Great Cave’ (Image: Adam Haydock)

They decided to make a dash to safety. Quickly, three of the divers who were still underwater were ushered out and they all headed towards an area known as the Whacking Great Chamber – a cathedral-like space nearly 100 metres high. If the team could get there they would be safe from drowning, but the water was rising fast and in the narrow passage leading to the chamber it was, at its worst, just 10cm from the rock ceiling.

Two of the divers plunged into the water and swam the ten metres required to ascertain that the route was safe. Having done so, they managed to run a line through the rapidly filling passage and the others quickly followed.

While they were temporarily safe in this vast chamber, the divers were now a kilometre away from their flooded exit. With just four granola bars between the six of them, the wetsuits they stood in and only one space blanket to provide any sort of warmth, the gravity of the situation began to sink in. Privately they all started asking themselves some daunting questions: what if it the water keeps rising? When, if ever, will it drop? Could the natural high water mark leave them trapped? How long have they got?

The team preparing to descend prior to becoming trapped (Image: Adam Haydock)

Gilly Elor, 33, from the United States, describes their predicament: ‘The only action we could take once trapped was to lie still in the dark, conserving both energy and headlamp batteries while attempting to keep warm.’ The only hope the team had was that the water level at the passage would drop. ‘We knew that was our only way out,’ says Elor.

But the water continued to rise. ’That first night nobody spoke a word,’ she remembers. ‘What would we have talked about? Our outside lives? I think we were all contemplating the possibility that we may not get out.’

Eventually, however, the water level began to slowly drop. The team continued to huddle in the dark, listening to the sound of the gurgling water and coming up with theories justifying why every noise was a good sign. But it was agonisingly slow going. ‘As time passed, we grew weaker from lack of food,’ describes Elor. ‘After 48 hours we split two of the four granola bars six ways. I think the trick in this situation is not to fantasise about the food you can’t have.’

It was 69 hours in total before the waters had dropped enough for the divers to finally escape and, exhausted and extremely hungry, they reached the cave exit after several hours of scrambling through passages that were now treacherous with mud. Still the challenge wasn’t over though as, having not eaten for three days, they had to ascend the 700 vertical metre canyon walls before finally reaching their base camp late at night.

The full story of the team’s expedition plus an account of their involvement with the rescue operation in Thailand will appear in the September print issue of Geographical, on sale from 23 August.